United and American are both better choices if you want to fly international widebodies. They are actually forging new routes on their own metal (ie United 787 to Chengdu). Direct flights cutting out hubs where possible that business travelers want to fly on.

Delta is trying to grow through partners and equity deals continuing the hub and spoke system at places like Beijing and Shanghia.

This is not too far removed from the money losing RJ experiment.... a total bust over the last decade. Delta will give all these airlines information on how to compete only to be cut out of the deal when the Chinese airlines (for example) decide to change the rules, push Delta out and go it alone. Delta will be the equivalent of US troops fighting against soldiers they trained in Iraq. By then more senior management will bail with their golden parachutes while the new set come in to try more experiments at the expense of long term employees. That's my two cents.